QF 4594 then AS 591 at San Francisco
Philadelphia → San Francisco → Seattle
Timetable, San Francisco time
19:28QF 4594 from Philadelphia at the gate
18:48AS 591 to Seattle leaves the gatealso QF 3787
23 h 20 apart on the timetable, overnight
AS 591 leaves 23 h 20 after QF 4594 arrives on the timetable: more than half a day, so not a connection we count.